The invention relates to vapor compression systems and, more particularly, to a system and method which allow for performance enhancement and discharge temperature reduction in an unloaded mode of operation of the vapor compression system.
Vapor compressor systems are widely used in air conditioning refrigeration and other applications, and involve a compressor, a condenser, an expansion device and an evaporator which serially treat refrigerant passed therethrough in a manner which is well known to a person of ordinary skill in the art.
It is further known that a vapor system with a bypass circuit can be used to direct a portion of refrigerant flow from an intermediate location along the compression process in the compressor back to the compressor inlet. This unloads the compressor, which is frequently desirable in non-peak demand conditions.
Although this unloading can help to provide more continuous and hence more efficient operation of the system, the need remains for further system efficiency improvement and it is the primary object of the present invention to provide same.
Another object of the present invention is to widen the compressor operating envelope and prevent nuisance system shut-downs as well as improve compressor reliability.